Distance Calculation Using Lookup Table for Nonlinear Waveforms
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for extracting distance information, such as the stereo vision and triangulation methods, face accuracy issues as the distance between an object and an optical apparatus increases, and require ideal waveforms which are difficult to achieve due to nonlinearity and operation errors in light sources and modulation devices, necessitating expensive waveform generators and complex algorithms.
Innovation Solution
A method using actual nonlinear waveforms to calculate distance by projecting multiple lights with different waveforms onto an object, modulating and detecting the reflected light, and employing a lookup table to determine the phase delay, allowing for accurate distance calculation without requiring ideal waveforms or expensive equipment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If ideal waveforms (triangular or sinusoidal) are assumed for distance calculation, then the calculation process is simplified, but measurement precision deteriorates due to waveform distortion from nonlinearity and operation errors in light sources and modulation devices
Solution Approach 1:
The patent pre-calculates and stores correction values in a lookup table by simulating various distorted waveforms and their corresponding distance errors. During actual measurement, the system simply queries this pre-computed table rather than performing complex real-time corrections, thus maintaining measurement precision while keeping the device complexity low.
Solution Approach 2:
The patent creates a computational model that copies and simulates the actual nonlinear behavior of light sources and modulation devices. By generating virtual distorted waveforms that match real device characteristics and pre-calculating their impact on distance measurements, the system captures complex nonlinear effects without requiring complex hardware or real-time computation.
2Measurement precision
If expensive waveform generators or complex error correction algorithms are used, then measurement precision improves, but device complexity and cost increase
Solution Approach 1:
The patent performs all complex waveform analysis and error characterization in advance during system setup or calibration. The results are stored in a simple lookup table that can be queried during normal operation. This shifts the computational burden from real-time operation to preliminary setup, enabling high precision measurements using simple, low-cost hardware.
Solution Approach 2:
The patent replaces expensive, high-precision waveform generators with ordinary, low-cost light sources and modulation devices. By compensating for their imperfections through the lookup table method rather than requiring inherently precise hardware, the system achieves high measurement accuracy using inexpensive components.
3Measurement precision
If multiple different lights with different waveforms are projected onto an object, then measurement precision improves by accounting for actual nonlinear waveforms, but device complexity increases due to need for multiple light sources and modulation control
Solution Approach 1:
The patent makes a single light source and modulation device perform multiple functions by sequentially projecting different waveform patterns. The same hardware component is used to generate various distorted waveforms (triangular, sinusoidal, and actual nonlinear waveforms) at different times, eliminating the need for multiple specialized light sources while still capturing the full range of device behavior for accurate distance calculation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables precise distance measurement across varying distances without the need for ideal waveforms, reducing the requirement for expensive equipment and complex algorithms, and allows for real-time distance information extraction.
Implementation Method 1
The TOF method involves emitting a laser beam to an object and measuring a time taken for light reflected from the object to be received by a receiving unit
Implementation Method 2
receiving part of the light having the wavelength of 850 nm reflected from the object by using a receiving unit
Data Source
AI summary
A method and apparatus for determining a distance between an optical apparatus and an object by considering a measured nonlinear waveform, as opposed to a mathematically ideal waveform. The method and apparatus may accurately calculate distance information without being affected by a type of waveform projected onto the object and may not require an expensive light source or a light modulator for generating a light with little distortion and nonlinearity. Further, since the method may be able to use a general light source, a general light modulator, and a general optical apparatus, additional costs do not arise. Furthermore, a lookup table, in which previously calculated distance information is stored, may be used, and thus the amount of computation required to be performed to calculate the distance is small, thereby allowing for quick calculation of the distance information in real time.